CVE intelligence

CVE-2026-46076

Vulnerability intelligence

Published May 27, 2026Sources checked Nov 11, 2026

7.9HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2026-46076 and is rated High severity with a CVSS score of 7.9. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Nov 5, 2026

Release Notes

CISA KEVNot listedBased on the latest collected catalog

EPSS0.1%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-46076?

In the Linux kernel, the following vulnerability has been resolved:

KVM: nSVM: Raise #UD if unhandled VMMCALL isn't intercepted by L1

Explicitly synthesize a #UD for VMMCALL if L2 is active, L1 does NOT want to intercept VMMCALL, nested_svm_l2_tlb_flush_enabled() is true, and the hypercall is something other than one of the supported Hyper-V hypercalls. When all of the above conditions are met, KVM will intercept VMMCALL but never forward it to L1, i.e. will let L2 make hypercalls as if it were L1.

The TLFS says a whole lot of nothing about this scenario, so go with the architectural behavior, which says that VMMCALL #UDs if it's not intercepted.

Opportunistically do a 2-for-1 stub trade by stub-ifying the new API instead of the helpers it uses. The last remaining "single" stub will soon be dropped as well.

[sean: rewrite changelog and comment, tag for stable, remove defunct stubs]

Source: NVD